Antithrombotic Therapy for Patients With Atrial Fibrillation and Bioprosthetic Valves　― Real-World Data From the Multicenter, Prospective, Observational BPV-AF Registry ―

BACKGROUND: Although bioprosthetic valve (BPV) replacements are becoming more common within our aging society, there are limited prospective data on the appropriate antithrombotic therapy for East Asian patients with atrial fibrillation (AF) and BPV replacement. Antithrombotic therapy and thrombotic and hemorrhagic event rates in Japanese patients with AF and BPV replacement are investigated. METHODS AND RESULTS: This multicenter, prospective, observational study enrolled patients with BPV replacement and AF. The primary efficacy outcome was stroke or systemic embolism, and the primary safety outcome was major bleeding. Of the 894 patients analyzed, 54.7%, 29.4%, and 9.6%, were treated with warfarin-based therapy, direct oral anticoagulant (DOAC)-based therapy, or antiplatelet therapy without anticoagulants, respectively; 6.3% did not receive any antithrombotic drugs. The mean observation period was 15.3±4.0 months. The event rates for stroke or systemic embolism and major bleeding were 1.95%/year and 1.86%/year, respectively. The multivariate adjusted hazard ratios for DOAC vs. warfarin were 1.02 (95% confidence intervals [CI], 0.30-3.41 [P=0.979]) for systemic embolic events and 0.96 (95% CI, 0.29-3.16 [P=0.945]) for major bleeding. CONCLUSIONS: Approximately 30% of patients with AF and BPV replacement were treated with DOAC. The risks of major bleeding and stroke or systemic embolism were similar between warfarin- and DOAC-treated patients with AF who had BPV replacement. Treatment with DOACs could be an alternative to warfarin in this population.